Lifting jack



Mafch 15, 1 927.

l. E. DEARSLEY LIFTING JACK Filed Deo, 4,l 1925 5 Sheets-sheet v1 March l5! 1927 l. E. DEARsLEY -LIFTING JACK f d f l e, n n n .11.. F

@L m Q .m (1mm 1,621,314 March 15, 192'?. LE. DEARSLEY l CHGTS- Paie-fea Ma. 151,927.

UNITED STATES PATE-NT OFFICE.;

IRWIN E. DEARsLnY, or -RACINE, WISCONSIN, ,AssIGNoa ro WALKER MANFACTUR- e ING COMPANY, or RACINE; wIsCoNsIN, A CoRroaA'rIoN or wIsCoNsIN.

' LUTING JACK.

Application led December 4, 1925. Serial No. 78,187. -l

This invention relates to lifting jacks, and morev particularly to a jack designed for use about garages and repair shops, for quickly and easily-lifting heavy loads, such as one end of an automobile, and transporting the elevated load from place to place..

In general, the jack comprises arather long, low truck or-carriage, supported at its ends on small rollers, all of the mechanism carried by the carriage being of very small height, or capable of being depressed to an extremely low position, so that the assembly can be pushed under very low hanging loads, such as' automobiles mounted on the new ballon tires. The forward end of the carriage, which is to be pushed under the load, carries the actual ,lifting mechanism of "the jack, while the driving and reversing mechanism for actuating the lifting jack in both directions is mounted at the extreme rear end of the carriage, so that it may be conveniently operated.

One object of the invention is to provide a jack of the type described, `which is ex-r tremely low, so as to operate beneath very low hanging loads, and at' the same time may be conveniently operated from a d istance. f 1

Another object is to provideV a new and -improved form of lifting inechanism having an extremely low initial position, and a relatively high operative rangeof, movement.

Another object is to provide an improved adjustablel operating handle, whereby the mechanism may be operated from a number of different convenient positions.

Another object is to provide an improved form of reversin mechanism, whereby the same movement o the operating handle may be used to elevart/e or lower the jack a's 'des'ired. 's

Another object is to provide an improved form vof foot operated mechanism for vquickly elevating the jack before the load is accepted. l

Another object is to provide an improved automatic reversing mechanism, whereby continuous operation ofthe .lifting handle willfcause the jack"to-be lowered after` it `has reached its extreme limit of elevation.

Numerous other objects and advantages of this invention willl be apparent .from the following detailed description vof 'one ap-v proved form of the apparatus.

Fig. 6 is a side elevation of the rear end of the Fic'. 1.

Fig. 7 is a vertical section, taken substantially on the line A 7-'7 of Figf4.

F lgs. 8 to 16 are detail views .of certain' jack, taken from the side opposite parts ofthe elevating and reversing mech-- anism showing the same elements in' diferr' i ent operating positions. Figs. 8 and 9 show the parts positioned for elevating the-jack,

whereas Figs. 10 to 16 inclusive show suc-,

cessive steps in the lowering rocess.

The frame 1 is built up o suitable'cast-- ings and connecting members-and of such a length that when the lifting end is posihoned beneath one of the axles of an automobile, the other' end on which is positioned the operating. mechanism, will extend out to an accessible position beyond the body of the ear. The ront or lifting end of the l.carriage 1 is supported upon a pair of rather small, but sturdy rollers 2, mounted on the ends of a transverse axle 3. The rear end of the carriage is supported by a pair of small rollers orcasters 4, pivoted .at the lower end of vertical'stub shafts 5, which are swiveled inl brackets 6 extending from the respective sides'of the carriage 1. These swiveled lcasters 4 permitv steering of lthe carriage, which can be swung 'around abruptlyinto any desired position.

The lifting headf has a screw threaded stem 8 mounted in a nut 9, which is seated.

in a recess in the lifting block 10. By manually rotating the load-carrying head 7, a certain amoim't of initial adjustment of the lifting headis permitted to adapt the device for loads of different character. lhe nut 9 may pivot in the block 10 at-all' times, thus permitting turning movementA of 'the car- 8 isl completely raised or lowered. A. lug `11 -riage beneath the load, even when the screw on block is pivoted on journal 12 between the forked end portions ofthe longer arm 13 of the bellcrank 14, which is suspended from and fulcrumed on the transverse shaft 15, which is mounted in the highest portions of the side members of frame4 or carriage 1. The shorter arm 16 of the bellcrank 14 is pivoted at 17 to the front end of the push rod or operating bar 18, which terminates near its rear end in a rack bar 19, which meshes with the driving pinion 20 hereinafter described. A lug 21 at the front 'of lifting block or head 10 is pivoted at'22 betweenlthe forward ends of a pair of similar links 23, the rear ends of the links being pivoted at 24' to the side members of frame 1. The spacing of shafts and 24 1s the same as that of journals 12 and 22, and the links 23 are of the same length as the longer arm 13 of the bellcrank, so tlat when lifting bellcrank 14 is swung about its pivot 15, the load supporting head 7 will be moved vertically, but :will remain horizontal at all times, one elevated position of the load supporting head being indicated in dotted lines in Fig. 3. It will be noted that when the load supporting head is in its completely lowered position, as indicated-in full .lines in Fig. 3, its upper surface 1s no higher than'the tops of the rollers 2, so that any load can be elevated under which .the supporting rollers 2 can be pushed.

,The driving pinion is fixed to a`transverse shaft 25, journaled in suitable Ibushings 26 and 27 in the side frames of the carriage 1. The rack bar l19 is slldably supported on a lower transverse bridge portion 28 of the carriage, whereby the rack is held up into engagement with the pinion 20. A yoke or housing 29 has its side arms pivoted about the axle at either side of the driving pinion 20. A ratchet wheel 30 is secured to the shaft 25 at one side of housing 29, and` a lifting awl 31 which cooperates with this ratchet w ,eelis mounted in an extension 32 at one side of the housing 29.` A spring 33 holds the pawl -31 yieldably in engagement with the ratchet 30. A locking pawl .34,

ivoted on transverse .shaft 35 in framel 1, 1s also held yieldably in engagement with ratchet 30 by means of spring 3 6. It will:

be noted that as the housing 29 is oscillated back and forth, through `a short arc, the ratchet 30 will be rotated intermittently in one direction (clockwise, Fig. 4), by. the driving pawl 31, andwill be held in advanced position against retrograde movement by the locking pawl v34. By means of a mechanism for controlling the pawls 31 and 34, hereinafter described, the same oscillatory movement of housing 29 may be used'to permit rotation of the ratchet 30 in the opposite direction.

The operating handlel v37, in the -form of side plates connected by suitable spacing members, has its lower ends'journaled at 38 on the projecting ends of shaft 25 at the outer sides of the frame 1. Handle 37 .is of sufficient length to be conveniently operated by a man standing' erect, and this handle is used both to oseillate the driving housing 29, and also to move the carriage 1 from place to place. A plunger 39, mounted vin a bridging member 40 in the handle 37, is normally projected by spring 41 into one of several holes `or openings 42, in the upper portion of yoke or housing 29'.' This plunger 39 serves to lock the housing 29 and operating handle 37 togethertooperate as a unit, and by roperly selecting the opening 42 with which the plunger is engaged, the inclination of the handle 37 may be variedto suit the convenience of the operator,

or to avoid' overhanging obstructions. A handle 43 at the upper end of plunger may be used to retract 'the plunger against the spring 41, and a guide arm 44 extends i back from the outer end of handle 43 through a suitable aperture in the bridge plate 40. When the plunger 39 is with- `i drawn, the handle 43 may be slightly rotated to bring the arm 44 out of alignment with the hole in bridge 40, whereby the arm 44 will cooperate with'bridge 40 to retain the plunger 39 in Withdrawn position'. `The handle 37 is then free to lswing up or down as far as desired for convenience in moving v the carriage 1 from one position to another.

The reversing member or plate 45 is freely pivoted about the axis of shaft 25 at the side of ratchet wheel 30 opposite the houslng 29. `Reversing plate 45 has a cam extension 46 atone side adapted to cooperatelwith a pin 47 on locking pawl 34 and h as a second cam extension 48. at the other side-of its axis, adapted to cooperate with a pin 49. on the liftin pawl 31. A compression sprug 51, co ed between a portion of the carriage 1. and a 'lug' 50 on thereversing member 45, tends to rotate the reversing member in a clockwise direction, (as

seen in, Figs. 8 to'16 inclusive), and movex ment of the reverslng plate in this direction is llmited by the engagement of lug 52011 the reversing plate with a fixed stop 53 oncarriage 1. When the 'ack is ito be elevated, reversmg member 45 1s l,held back against the action of spring 50 so that cams 46 and 48 will not encounter the pins 47 and 49 on the pawls 34 and 31. This position ofthe parts is indicated in Figs. 8 and 9. As best indicated in Fig. 6, a cam or crank'arm 54,

pivoted in the vcarriage y frame at, 55,' is

adapted to be moved k'up behind the lug 56 on the reversing Ir 1ember .45,` to hold this member in inoperativeposition as in Figs. 8 and 9. A secondcrank arm 57, connected with cam 54, has a pin 58 at its free end engaging in a slot 59 in one arm of a edal `lever `60, pivoted on the end of sha t 25.

arm of lever 60, the bellcrank composedl of crank arms 54 and 57, is thrown up into the position indicated in Fig. 6, bringing the cam 54 behind the lug 56, and moving the reversing plate 45 against the action of spring 51, to its inoperative position. Os-

,clllating movement of hand lever 37 .will

then serve torotate ratchet 30 `in a clockwlse4 direction, as seenin Figs. 8 and 9, to effect an 'elevation of the jack., It will be under'- stood that the load carried by the supporting head 7, acting through bellcrank 14 and push-rod 18 and rack bar 19, constantly tends` to rotate the driving pinion 20 and the ratchet wheel in a counter clockwise direction, as shown in Figs. 8 to 16 inclusive. As shown in Fig. 8, the handle 37 has been elevated, and the locking pawl 34 is in engagement with a tooth of ratchet 30 and is .holding the load. As the hand lever 37 is swung down from' the position shown in- F ig.- 8 to that shown in Fig. 9,l the lifting pawl 31 will be brought into engagement with' a tooth or ratchet wheel 30 and will partially rotate this ratchet, the locking pawl 34 riding up against the action of spring 36 until it snaps into engagementwith t When hand lever 37 is'swung back up to the position shown in Fig. 8, the ratchet 30 will be held against retrograde movement by the locking pawl 34 and the lifting pawl 3l will ride out-against the action of spring 33 until it snaps into engagement with the next following pawl on the ratchet wheel. Successive oscillations of the operating handle 37 will repeat this cycle of events, ad-

vancing the ratchet 30 each time through an arc equal to one tooth of the ratchet wheel. Obviously, the, parts could be so proportioned that this advance would be through an arc equal to a plurality of teeth.v

Referring now to Figs. 10 to 16. successive steps in the lowering process will be described. 'It should be 'understood that the reversing plate 45 is now released from the cam-54, so that it is free to swing in a clockwise. direction under the influence of spring 51. As shown in Fig. 10, the lload is being' held by the locking pawl 34, which is in engagement with a tooth of ra et 30, and

the cam 46 on the reversing plate 45 isheld up against lthe pin 47 on pawl 34, by the Vspring 51. The hand `lever 37 is being swung down and pin 49A on lifting pawl 31 has just snapped. off from the'end of cam 48 permitting the end of the lifting pawl to engage with one of theteeth on `ratchet 30 near its upper slrface.. Further downward movement of handle 37 will cause the pawl 31 to slide down the inclined surface of this tooth until it engages with the nex't successive tooth and accepts the load. Aslightfurther-clockwise or downward movement e next following tooth of the ratchet.'

which will now be snapped out to an inoperative position by the cam 46 acting under the influence of spring 50. This position of the parts is shown in Fig. 11. It will be noted that the reversing plate 45 has been swung in a clockwise direction until the stop lug 52 has engaged with the ixedfs/top 53, but the cam 48 is lstill out of engagement with the pin 49 on lifting pawl 31. 'The load is now held by the lifting pawl 31 and handle 3L The hand lever 37 is now elevated, allowing the ratchet wheel 30 to move back with it in a counter clockwise direction. During this upward movement, the pin 49 on pawl 31 first comes into engagement with the cam 48, as shown in Fig.` 12.' and'subsequent upward movement of these parts,

'causes the reversing plate 45 to share the counter clockwiserotation of the ratchet 30,

gradually moving .the cam 46 down out of engagement with the pin 47 on locking pawl 34, as^shown in. Fig. 13. lEventually the locking pawl 34 will engage with the tooth .of lthe ratchet 'wheel next following that Withwhich it was previously engaged, and

ing lever 37. As we start down again on the succeeding downward swing of the operatinglever, pin 49.will ride oli from the cam 48 allowing. the spring' 33 to bring .the lifting pawl back into engagement with the ratchet as indicated vin Fig. 16, from which position of the arts they move directly to 'the initial position shown in Fig. 10, and

the cvcle of events just described is repeated.

It will thus be seen that successive oscillations of the operating handle 37 will cause the load to be lowered. step by step, just as it was elevated by similar movements of the .the limit of the upward swing of the operatlll) operating handle whenthe reversing mem-4 ber was in inoperative Figs. 6,831.1(19. L

vProjecting from one side of the extreme` rear end of rack bar 19 is a lug 64, which, upon extreme inward movement of fthe rack bar will engage -with one arm 65 of a lever centrally pivoted at 66 in the carriage frame,

the other arm \67 of this leverresting in engagement with a pin 68 on one side of cam 54. Further inward movement of the rack bar and lug .64 will swing the lever 65 in a clockwise direction, as seen in Fig. 6 and push the cam 54 down out of engagement with the lug 56, thu's releasing the reversing position as shown in member 45, so that successive operations of the operating handle 37 will cause the load to be lowered as hereinabove described. The cam 54 may be manuallyreleased at any time by pushing pedal 63 to the right as v shown in Fig. 6.

On the opposite end ofthe drive lshaft is secured 'a paddle wheel 69, comprising a plurality, (preferably four), of spaced.. arms 70, each having a pedal 71 at its outer end whereby a pressure of the foot on one of the pedals will give a partial clockwiserotation to the shaft y25. Although Y the leverage is small. this mechanism isadapted to quickly .bring the lifting heady '7 up to meet the load, after which the actual elevation of the load is carried on by means of thelonger hand-lever 37. I

In the general operation of this device the front end of the jack is shoved into position beneath the load by suitably manipulating the operating handle 37'.` If the load to be elggaged is somewhat l higher than usual driving pinion 20 pushes the rack bar 19 na ove the floor or other supporting surface, the supportinghead 7 is first rotated within the nut 9 to elevate this head above the supporting block 10 before the jack is pushed into position beneath the. load. ANow by successively pushing down -uponthe pedals 71 the mechanism may be quickly operated to bring the supporting head 7 up into engagement. with the loadl The rotation `of wardly or forwardly, thus swinging up the front end of bellcrank 14 and elevating the head 7. After the load has been accepted, further elevation is accomplished by oscillating the khand lever 37 through/a, short arc. For this opera-tion, they handle 37 may be positioned at a convenient angle by withdrawing' the plunger 39, by means of handle 43, and placing this plunger in thatopening 42 which will leave the handle at the lmost favorable angle. If the reversing member 45 is in operative position, it may be thrown out by depressing the pedal 61 to the position showny in Fig. 6. Then the load has f housing 29 byw'ithdrawing the plunger 39' beenelevated tothe desired position, itA will be heldfin this position by the locking pawl 34. If thev load is to be moved bodily, as when one end of an automobile is to be shift(- ed to a' different position in a garage, the jack and the load carried'thereby may be `moved as desired by means of the handle 37, which may be kept locked to housing 29 or conveniently released from theoperating and positioning the arm 44 against the bridge member 40, thusLolding the plunger 39 ,in

retracted position'. When it isl desired to -lower the load, it is only necessary to push over -the 'pedal 63, thus releasing the revers- `ing plate 45, so that subsequent reciprocation or oscillation of the operating handle 37 will cause the load to belowered. step by step.

. around with ease;

It the load has beenelevated to'or^ near the extreme upward limitv of the jacks movement, it will be unnecessary to manipulate the pedal 63, since continuous oscillation of the hand lever 37. will bring the lug 64 on rack 19 int-o engagement with lever 65, thus automatically throwing the reversing member into operative position.

Theoscillatory `travel of the housing 29. is limited at the end of the downward stroke by the engagement of the lug' 72 on housing 29 (see Fig. 8), with the floor 73 of the bsidge member 28 offrame 1 (see Fig. ,7), and at the end of the upward stroke by the engagement of the top of lug 72 with an upper portion of the frame 1. This limits thel -motion of the handle 37 to avcomparatively small arc when it is locked to the housing 29 by rthe plunger39, and is of great assistance to the operator when placing the 'ack in any position -under a load, for by a s ort movement up or down of the handle 37, a contact is formed with the main-frame 1, thus establishin' a rigid unit which may be moved A safety feature that should not be overlooked is that when the operator has the load lifted and desires to work underneath it,

he can, by pulling the plunger 39 out of hole' means to an inoperative position, and a lever pivoted on the axis of the reversing member and adapted to operate the cam.

2. In a lifting jack, an elevating and lowering mechanism comprising a pivoted reversing member, a pair of lugs on the member, a means engaging one lug to automatically rotate the member to an operative position, a rotary cam adapted to be swung into position "behind the other lug to move the Y reversing member 'to inoperative position and lock 1t there, a crank-arm on the cam, and a lever ivoted on the axls'of thereversingmem er 'and having an operating.

connection with the crank arm to swing the cam into or out of engagement with the lug.

3. In a lifting jack,the combination with arr elevating and lowering mechanism including a. ratchet wheel, a lifting pawl and a locking pawl enga-geable with the ratchet,

springs for normally holding these pawls in engagement with the ratchet, and means-forA oscillating'the lifting pawl about the pe'-l riphery of the ratchet,- of areversng mem- 1. In a lifting ber pivoted on the axis of the ratchet and havinga pair of cams adapted to alternately move the pawls out of engagement with the ratchet. t 4

jack, the combination with an elevating and lowering mechanism in.- cluding a ratchet wheel, a lifting pawl and a locking pawl engageable with the ratchet, and means Ifor oscillating the lifting pawl about the periphery of the ratchet, of a reversing member pivoted on the axis of the ratchet and having a pair of cams adapted to alternately move the pawls out of enga ement with Athe ratchet, and a means or urging thereversing member in one direc-- tlon. f Y

' 5. In a .lifting jack, the combination with an elevating and lowering mechanism includmg a ratchet wheel` a lifting pawl and a locking pawl engageable with the ratchet,

means for oscillating the lifting pawl about the periphery of the ratchet, of a reversing member pivoted o'n the axis of the ratchet and having a pair of cams adapted to a'.-

nnitely move the pawls out ofengageme'nt with the ratchet, ,a spring for movingv the reversing member 1n one direction,` a stop for "limiting-this movemen of 'the reversing member, and means for locking the reversing 3e member in retracted position against the action of the spring.

6. In a liftingV jack, the combination -with an elevating and lowering mechanism including a ratchet wheel, a lifting pawl and a locking pawl engageable with the ratchet,

means for oscillating the lifting pawl about the periphery of the ratchet, of a reversing member pivoted on the axis of the ratchet and having a pair of cams adapted to, alternately 40- move the pawls out of engagement with the lratchet, a means for moving the reversing member t'o'operative position, a lug on the' member, and a cam movable behind the lug to lock the reverslng member in inoperative position. 1

7 In a lifting jack, the combination with an elevating and lowering mechanism 'including a ratchet wheel, a lifting pawl and al locking. pawl engageable with the ratchet,

50. means for oscillating the lifting pawl about the periphery of the ratchet, of a reversing member pivoted on `the axis of the ratchet' and having a pair of cams adapted to alternately move the pawls out of engagement with the ratchet, a means for moving the reversing member to operative posit-ion, -a lug on the member, a rotatable cammovable behind the lug to lock lthe reversing mem` ber in inoperative position, and a lever for shifting the cam.

8. In a lifting jack, the' combination with an v'elevating and lowerin mechanism including a ratchet wheel, a lifting pawl and a locking pawl each having an outstanding projection, springs for yieldably holdingy o5 f .each pawl 1n engagement with the-ratchet,

and means for moving the lifting awl back and forth about the periphery of t 1e ratchet,

of a reversing member pivoted on the axis and means for moving the lifting pawl back and forth about the periphery of the ratchet, of a reversing member pivoted on the axis 'cf the ratchet 4and having a pair of cam surfaces adapted to alternately engage the pro. jections to movev one or, the other of the pawls out of engagement with the ratchet.

l0. In a lifting jack, the combination with an elevating and lowering mechanism including a ratchet wheel, a lifting pawl and a locking pawl each having an outstanding projection, springs .for yieldably holding each pawl in engagement with the ratchet, means for moving the lifting pawl back and forth about the periphery of the ratchet, of a reversing member pivoted on the axis of the ratchet and having a pair of cam surfaces adapted to alternately engage the prof jection to move one or the other of the pawls va reversing member pivoted on the axis of the ratchet and having a pair of cam surfaces adap'ted to alternately engage the projections to move one or the other of the pawls out of engagement with the ratchet, a pair of lugs on the reversing member, a spring engaging one lug to move the revers-- vmg member in one direction, and a locking cam Vengageable' with the other lug to move the reversing member in the opposite direc? .A

12. Ina lifting jack, an elevating and lowering mechanismicomprising a longitu dinally movable member and rotary means for moving this member in either direction, I

a. reversing member cooperating with the i. rotary means to determine the direction of movement Aof the longitudinally. movable member, and means on theJ longitudinally movable member for rendering the reversing 'member operative when the longitudinally movable member reacliesits limit of movement in one direction.

13. In a lifting jack, an elevating` and lowering mechanism comprising a longitudinally lmovable ymember and `iotary means for moving this member in4 either direction,

a reversing member cooperating with the rotary means to determine the direction of movement of the longitudinally movable member, means for locking the reversing member in inoperative position,` and means on the longitudinally movable member for unlocking the locking means.

14. In a lifting jack, an elevating and llowering mechanism comprising a longitudinally movable rack-bar, a rotary shaft,

a pinion on the shaft meshing with the rack,

a' pawl and ratchet mechanism for rotating the pinion, a reversing member pivoted about the shaft for controlling the direction of rotation` of the pinion, a cam for locking the reversing member in inoperative posii tion, a lever for releasing the cam, and a lug on the rack-bar engaging the lever in one position of the rac 15. In a lifting jack, an elevating and lowering mechanism comprising a longitudinally movable rack-bar, ,arotary shaft, a

pinion on the shaft meshing with the rack, a pawl and ratchet mechanismfor rotating the pinion, a reversin member pivoted aboutpthe shaft for-controlling the direction of rotation of`the pinion, a cam for locking the reversing member in inoperative position, and means operated by the rack-bar at one extremity of its movement for releasing 16. Inafliftinfg jack,- an elevating and `lowering mechanism comprising allongitu-4 dinally movable rack-bar, a.rotary shaft, a

pinion on the shaft meshing with the rack, a pawl and ratchetl mechanism for`rotating the pinion, and an auxiliary means for rotatingthe pinion .comprising a pluralityof radztilly extending crank-armssecured to the sha 17. In a lifting jack, an elevating and lowering mechanism comprising a longitudinally movable rack-bar, a rotary shaft, a pinion on, the shaft meshing Witliihe rack, and a pawl and ratchet mechanism for rotating the pinion, and an auxiliary means shaft, and means for locking the handle to the memberin different selected positions.

20. In a lifting jack, an elevating and lowering mechanism com rising a rotary shaft, an oscillatable memiier pivoted about the axis of this shaft for adtuating the ele- .vating means, an operating handle also pivoted about the axis ofthe shaft, a spring-- pressed plunger carried by the handle, a

l plurality of openings in the oscillatable member to be selectively engaged by the plunger, and a locking means for holding the plunger Withdrawn fromV the openings against the'action of the spring.

21. In a lifting jack,l an elevating-and v loyv/ering mechanism comprising a rotary shaft, an oscillatable meniberpivoted about 'the axis of this shaft for actuating the elevating means, an operating handlealso pivoted'about vthe axis of the shaft, a springpressed plunger carried by the handle, a plurality of openings in the oscillatable 'member to be selectively engaged by the plunger, and a' handle onthe plunger for vithdrawing it from an opening, the handle eing drawn position.

IRWIN? E. DEARsLEY.

movable to lock the plunger in With- Y Cil 

